Revised handling of missing data class arguments

Includes unified detection of Kotlin's optional parameters in MethodParameter.isOptional(), reduces BeanUtils.findPrimaryConstructor to Kotlin semantics (for reuse in AutowiredAnnotationBeanPostProcessor), and finally introduces a common KotlinDetector delegate with an isKotlinType(Class) check.

Issue: SPR-15877
Issue: SPR-16020
This commit is contained in:
Juergen Hoeller 2017-09-28 00:31:12 +02:00
parent d3129a8bd7
commit ec345bf162
14 changed files with 204 additions and 344 deletions

View File

@ -18,7 +18,6 @@ package org.springframework.beans;
import java.beans.PropertyDescriptor;
import java.beans.PropertyEditor;
import java.lang.annotation.Annotation;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
@ -42,6 +41,7 @@ import kotlin.reflect.jvm.ReflectJvmMapping;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.KotlinDetector;
import org.springframework.core.MethodParameter;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
@ -70,21 +70,6 @@ public abstract class BeanUtils {
private static final Set<Class<?>> unknownEditorTypes =
Collections.newSetFromMap(new ConcurrentReferenceHashMap<>(64));
@Nullable
private static final Class<?> kotlinMetadata;
static {
Class<?> metadata;
try {
metadata = ClassUtils.forName("kotlin.Metadata", BeanUtils.class.getClassLoader());
}
catch (ClassNotFoundException ex) {
// Kotlin API not available - no special support for Kotlin class instantiation
metadata = null;
}
kotlinMetadata = metadata;
}
/**
* Convenience method to instantiate a class using its no-arg constructor.
@ -127,7 +112,7 @@ public abstract class BeanUtils {
throw new BeanInstantiationException(clazz, "Specified class is an interface");
}
try {
Constructor<T> ctor = (useKotlinSupport(clazz) ?
Constructor<T> ctor = (KotlinDetector.isKotlinType(clazz) ?
KotlinDelegate.findPrimaryConstructor(clazz) : clazz.getDeclaredConstructor());
if (ctor == null) {
throw new BeanInstantiationException(clazz, "No default constructor found");
@ -174,7 +159,7 @@ public abstract class BeanUtils {
Assert.notNull(ctor, "Constructor must not be null");
try {
ReflectionUtils.makeAccessible(ctor);
return (useKotlinSupport(ctor.getDeclaringClass()) ?
return (KotlinDetector.isKotlinType(ctor.getDeclaringClass()) ?
KotlinDelegate.instantiateClass(ctor, args) : ctor.newInstance(args));
}
catch (InstantiationException ex) {
@ -191,6 +176,28 @@ public abstract class BeanUtils {
}
}
/**
* Return the primary constructor of the provided class. For Kotlin classes, this
* returns the Java constructor corresponding to the Kotlin primary constructor
* (as defined in the Kotlin specification). Otherwise, in particular for non-Kotlin
* classes, this simply returns {@code null}.
* @param clazz the class to check
* @since 5.0
* @see <a href="http://kotlinlang.org/docs/reference/classes.html#constructors">Kotlin docs</a>
*/
@SuppressWarnings("unchecked")
@Nullable
public static <T> Constructor<T> findPrimaryConstructor(Class<T> clazz) {
Assert.notNull(clazz, "Class must not be null");
if (KotlinDetector.isKotlinType(clazz)) {
Constructor<T> kotlinPrimaryConstructor = KotlinDelegate.findPrimaryConstructor(clazz);
if (kotlinPrimaryConstructor != null) {
return kotlinPrimaryConstructor;
}
}
return null;
}
/**
* Find a method with the given method name and the given parameter types,
* declared on the given class or one of its superclasses. Prefers public methods,
@ -331,40 +338,6 @@ public abstract class BeanUtils {
return targetMethod;
}
/**
* Return the primary constructor of the provided class. For Java classes, it returns
* the single or the default constructor if any. For Kotlin classes, it returns the Java
* constructor corresponding to the Kotlin primary constructor (as defined in
* Kotlin specification), the single or the default constructor if any.
*
* @param clazz the class to check
* @since 5.0
* @see <a href="http://kotlinlang.org/docs/reference/classes.html#constructors">Kotlin docs</a>
*/
@SuppressWarnings("unchecked")
@Nullable
public static <T> Constructor<T> findPrimaryConstructor(Class<T> clazz) {
Assert.notNull(clazz, "Class must not be null");
if (useKotlinSupport(clazz)) {
Constructor<T> kotlinPrimaryConstructor = KotlinDelegate.findPrimaryConstructor(clazz);
if (kotlinPrimaryConstructor != null) {
return kotlinPrimaryConstructor;
}
}
Constructor<T>[] ctors = (Constructor<T>[]) clazz.getConstructors();
if (ctors.length == 1) {
return ctors[0];
}
else {
try {
return clazz.getDeclaredConstructor();
}
catch (NoSuchMethodException ex) {
return null;
}
}
}
/**
* Parse a method signature in the form {@code methodName[([arg_list])]},
* where {@code arg_list} is an optional, comma-separated list of fully-qualified
@ -712,15 +685,6 @@ public abstract class BeanUtils {
}
}
/**
* Return true if Kotlin is present and if the specified class is a Kotlin one.
*/
@SuppressWarnings("unchecked")
private static boolean useKotlinSupport(Class<?> clazz) {
return (kotlinMetadata != null &&
clazz.getDeclaredAnnotation((Class<? extends Annotation>) kotlinMetadata) != null);
}
/**
* Inner class to avoid a hard dependency on Kotlin at runtime.
@ -736,13 +700,13 @@ public abstract class BeanUtils {
@Nullable
public static <T> Constructor<T> findPrimaryConstructor(Class<T> clazz) {
try {
KFunction<T> primaryConstructor = KClasses.getPrimaryConstructor(JvmClassMappingKt.getKotlinClass(clazz));
if (primaryConstructor == null) {
KFunction<T> primaryCtor = KClasses.getPrimaryConstructor(JvmClassMappingKt.getKotlinClass(clazz));
if (primaryCtor == null) {
return null;
}
Constructor<T> constructor = ReflectJvmMapping.getJavaConstructor(primaryConstructor);
Constructor<T> constructor = ReflectJvmMapping.getJavaConstructor(primaryCtor);
Assert.notNull(constructor,
() -> "Failed to find Java constructor corresponding to Kotlin primary constructor: " + clazz.getName());
() -> "Failed to find Java constructor for Kotlin primary constructor: " + clazz.getName());
return constructor;
}
catch (UnsupportedOperationException ex) {
@ -765,9 +729,9 @@ public abstract class BeanUtils {
List<KParameter> parameters = kotlinConstructor.getParameters();
Map<KParameter, Object> argParameters = new HashMap<>(parameters.size());
Assert.isTrue(args.length <= parameters.size(),
"The number of provided arguments should be less of equals than the number of constructor parameters");
"Number of provided arguments should be less of equals than number of constructor parameters");
for (int i = 0 ; i < args.length ; i++) {
if (!(parameters.get(i).isOptional() && (args[i] == null))) {
if (!(parameters.get(i).isOptional() && args[i] == null)) {
argParameters.put(parameters.get(i), args[i]);
}
}

View File

@ -34,10 +34,6 @@ import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import kotlin.jvm.JvmClassMappingKt;
import kotlin.reflect.KFunction;
import kotlin.reflect.full.KClasses;
import kotlin.reflect.jvm.ReflectJvmMapping;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
@ -123,22 +119,6 @@ import org.springframework.util.StringUtils;
public class AutowiredAnnotationBeanPostProcessor extends InstantiationAwareBeanPostProcessorAdapter
implements MergedBeanDefinitionPostProcessor, PriorityOrdered, BeanFactoryAware {
@Nullable
private static final Class<?> kotlinMetadata;
static {
Class<?> metadata;
try {
metadata = ClassUtils.forName("kotlin.Metadata", AutowiredAnnotationBeanPostProcessor.class.getClassLoader());
}
catch (ClassNotFoundException ex) {
// Kotlin API not available - no Kotlin support
metadata = null;
}
kotlinMetadata = metadata;
}
protected final Log logger = LogFactory.getLog(getClass());
private final Set<Class<? extends Annotation>> autowiredAnnotationTypes = new LinkedHashSet<>();
@ -303,12 +283,9 @@ public class AutowiredAnnotationBeanPostProcessor extends InstantiationAwareBean
List<Constructor<?>> candidates = new ArrayList<Constructor<?>>(rawCandidates.length);
Constructor<?> requiredConstructor = null;
Constructor<?> defaultConstructor = null;
Constructor<?> kotlinPrimaryConstructor = null;
if (useKotlinSupport(beanClass)) {
kotlinPrimaryConstructor = KotlinDelegate.findPrimaryConstructor(beanClass);
}
Constructor<?> primaryConstructor = BeanUtils.findPrimaryConstructor(beanClass);
for (Constructor<?> candidate : rawCandidates) {
if (kotlinPrimaryConstructor != null && candidate.isSynthetic()) {
if (primaryConstructor != null && candidate.isSynthetic()) {
continue;
}
AnnotationAttributes ann = findAutowiredAnnotation(candidate);
@ -366,10 +343,10 @@ public class AutowiredAnnotationBeanPostProcessor extends InstantiationAwareBean
else if (rawCandidates.length == 1 && rawCandidates[0].getParameterCount() > 0) {
candidateConstructors = new Constructor<?>[] {rawCandidates[0]};
}
else if (kotlinPrimaryConstructor != null) {
else if (primaryConstructor != null) {
candidateConstructors = (defaultConstructor != null ?
new Constructor<?>[] {kotlinPrimaryConstructor, defaultConstructor} :
new Constructor<?>[] {kotlinPrimaryConstructor});
new Constructor<?>[] {primaryConstructor, defaultConstructor} :
new Constructor<?>[] {primaryConstructor});
}
else {
candidateConstructors = new Constructor<?>[0];
@ -381,15 +358,6 @@ public class AutowiredAnnotationBeanPostProcessor extends InstantiationAwareBean
return (candidateConstructors.length > 0 ? candidateConstructors : null);
}
/**
* Return true if Kotlin is present and if the specified class is a Kotlin one.
*/
@SuppressWarnings("unchecked")
private static boolean useKotlinSupport(Class<?> clazz) {
return (kotlinMetadata != null &&
clazz.getDeclaredAnnotation((Class<? extends Annotation>) kotlinMetadata) != null);
}
@Override
public PropertyValues postProcessPropertyValues(
PropertyValues pvs, PropertyDescriptor[] pds, Object bean, String beanName) throws BeanCreationException {
@ -771,32 +739,4 @@ public class AutowiredAnnotationBeanPostProcessor extends InstantiationAwareBean
}
}
/**
* Inner class to avoid a hard dependency on Kotlin at runtime.
*/
private static class KotlinDelegate {
/**
* Return the Java constructor corresponding to the Kotlin primary constructor if any.
* @param clazz the {@link Class} of the Kotlin class
* @see <a href="http://kotlinlang.org/docs/reference/classes.html#constructors">http://kotlinlang.org/docs/reference/classes.html#constructors</a>
*/
@Nullable
public static <T> Constructor<T> findPrimaryConstructor(Class<T> clazz) {
try {
KFunction<T> primaryConstructor = KClasses.getPrimaryConstructor(JvmClassMappingKt.getKotlinClass(clazz));
if (primaryConstructor == null) {
return null;
}
Constructor<T> constructor = ReflectJvmMapping.getJavaConstructor(primaryConstructor);
Assert.notNull(constructor, "Can't get the Java constructor corresponding to the Kotlin primary constructor of " + clazz.getName());
return constructor;
}
catch (UnsupportedOperationException ex) {
return null;
}
}
}
}

View File

@ -34,11 +34,11 @@ import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.InjectionPoint;
import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
import org.springframework.core.GenericTypeResolver;
import org.springframework.core.KotlinDetector;
import org.springframework.core.MethodParameter;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.core.ResolvableType;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
/**
* Descriptor for a specific dependency that is about to be injected.
@ -51,22 +51,6 @@ import org.springframework.util.ClassUtils;
@SuppressWarnings("serial")
public class DependencyDescriptor extends InjectionPoint implements Serializable {
@Nullable
private static final Class<?> kotlinMetadata;
static {
Class<?> metadata;
try {
metadata = ClassUtils.forName("kotlin.Metadata", DependencyDescriptor.class.getClassLoader());
}
catch (ClassNotFoundException ex) {
// Kotlin API not available - no Kotlin support
metadata = null;
}
kotlinMetadata = metadata;
}
private final Class<?> declaringClass;
@Nullable
@ -183,22 +167,14 @@ public class DependencyDescriptor extends InjectionPoint implements Serializable
if (this.field != null) {
return !(this.field.getType() == Optional.class || hasNullableAnnotation() ||
(useKotlinSupport(this.field.getDeclaringClass()) && KotlinDelegate.isNullable(this.field)));
(KotlinDetector.isKotlinType(this.field.getDeclaringClass()) &&
KotlinDelegate.isNullable(this.field)));
}
else {
return !obtainMethodParameter().isOptional();
}
}
/**
* Return true if Kotlin is present and if the specified class is a Kotlin one.
*/
@SuppressWarnings("unchecked")
private static boolean useKotlinSupport(Class<?> clazz) {
return (kotlinMetadata != null &&
clazz.getDeclaredAnnotation((Class<? extends Annotation>) kotlinMetadata) != null);
}
/**
* Check whether the underlying field is annotated with any variant of a
* {@code Nullable} annotation, e.g. {@code javax.annotation.Nullable} or

View File

@ -17,7 +17,6 @@
package org.springframework.beans.factory.support;
import java.beans.ConstructorProperties;
import java.lang.annotation.Annotation;
import java.lang.reflect.Constructor;
import java.lang.reflect.Executable;
import java.lang.reflect.Method;
@ -32,11 +31,6 @@ import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;
import kotlin.reflect.KFunction;
import kotlin.reflect.KParameter;
import kotlin.reflect.jvm.ReflectJvmMapping;
import org.springframework.beans.BeanMetadataElement;
import org.springframework.beans.BeanWrapper;
@ -82,22 +76,6 @@ class ConstructorResolver {
private static final NamedThreadLocal<InjectionPoint> currentInjectionPoint =
new NamedThreadLocal<>("Current injection point");
@Nullable
private static final Class<?> kotlinMetadata;
static {
Class<?> metadata;
try {
metadata = ClassUtils.forName("kotlin.Metadata", ConstructorResolver.class.getClassLoader());
}
catch (ClassNotFoundException ex) {
// Kotlin API not available - no Kotlin support
metadata = null;
}
kotlinMetadata = metadata;
}
private final AbstractAutowireCapableBeanFactory beanFactory;
@ -818,8 +796,8 @@ class ConstructorResolver {
* Template method for resolving the specified argument which is supposed to be autowired.
*/
@Nullable
protected Object resolveAutowiredArgument(
MethodParameter param, String beanName, @Nullable Set<String> autowiredBeanNames, TypeConverter typeConverter) {
protected Object resolveAutowiredArgument(MethodParameter param, String beanName,
@Nullable Set<String> autowiredBeanNames, TypeConverter typeConverter) {
if (InjectionPoint.class.isAssignableFrom(param.getParameterType())) {
InjectionPoint injectionPoint = currentInjectionPoint.get();
@ -828,18 +806,8 @@ class ConstructorResolver {
}
return injectionPoint;
}
boolean required = !(useKotlinSupport(param.getContainingClass()) && KotlinDelegate.isOptional(param));
return this.beanFactory.resolveDependency(
new DependencyDescriptor(param, required), beanName, autowiredBeanNames, typeConverter);
}
/**
* Return true if Kotlin is present and if the specified class is a Kotlin one.
*/
@SuppressWarnings("unchecked")
private static boolean useKotlinSupport(Class<?> clazz) {
return (kotlinMetadata != null &&
clazz.getDeclaredAnnotation((Class<? extends Annotation>) kotlinMetadata) != null);
new DependencyDescriptor(param, true), beanName, autowiredBeanNames, typeConverter);
}
static InjectionPoint setCurrentInjectionPoint(@Nullable InjectionPoint injectionPoint) {
@ -947,37 +915,4 @@ class ConstructorResolver {
}
}
/**
* Inner class to avoid a hard dependency on Kotlin at runtime.
*/
private static class KotlinDelegate {
/**
* Check whether the specified {@link MethodParameter} represents an optional Kotlin parameter or not.
*/
public static boolean isOptional(MethodParameter param) {
Method method = param.getMethod();
Constructor<?> ctor = param.getConstructor();
int index = param.getParameterIndex();
KFunction<?> function = null;
if (method != null) {
function = ReflectJvmMapping.getKotlinFunction(method);
}
else if (ctor != null) {
function = ReflectJvmMapping.getKotlinFunction(ctor);
}
if (function != null) {
List<KParameter> parameters = function.getParameters();
return parameters
.stream()
.filter(p -> KParameter.Kind.VALUE.equals(p.getKind()))
.collect(Collectors.toList())
.get(index)
.isOptional();
}
return false;
}
}
}

View File

@ -1,5 +1,5 @@
/*
* Copyright 2002-2013 the original author or authors.
* Copyright 2002-2017 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@ -18,7 +18,6 @@ package org.springframework.beans;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
@ -275,23 +274,6 @@ public class BeanUtilsTests {
}
}
}
@Test
public void testFindDefaultConstructorAndInstantiate() {
Constructor<Bean> ctor = BeanUtils.findPrimaryConstructor(Bean.class);
assertNotNull(ctor);
Bean bean = BeanUtils.instantiateClass(ctor);
assertNotNull(bean);
}
@Test
public void testFindSingleNonDefaultConstructorAndInstantiate() {
Constructor<BeanWithSingleNonDefaultConstructor> ctor = BeanUtils.findPrimaryConstructor(BeanWithSingleNonDefaultConstructor.class);
assertNotNull(ctor);
BeanWithSingleNonDefaultConstructor bean = BeanUtils.instantiateClass(ctor, "foo");
assertNotNull(bean);
assertEquals("foo", bean.getName());
}
private void assertSignatureEquals(Method desiredMethod, String signature) {
assertEquals(desiredMethod, BeanUtils.resolveSignature(signature, MethodSignatureBean.class));

View File

@ -66,26 +66,6 @@ class BeanUtilsKotlinTests {
assertEquals(12, baz.param2)
}
@Test
fun `2 constructors with default one`() {
assertEquals(TwoConstructorsWithDefaultOne::class.java.getDeclaredConstructor(), BeanUtils.findPrimaryConstructor(TwoConstructorsWithDefaultOne::class.java))
}
@Test
fun `2 constructors without default one`() {
assertNull(BeanUtils.findPrimaryConstructor(TwoConstructorsWithoutDefaultOne::class.java))
}
@Test
fun `1 constructor with default one`() {
assertEquals(OneConstructorWithDefaultOne::class.java.getDeclaredConstructor(), BeanUtils.findPrimaryConstructor(OneConstructorWithDefaultOne::class.java))
}
@Test
fun `1 constructor without default one`() {
assertEquals(OneConstructorWithoutDefaultOne::class.java.getDeclaredConstructor(String::class.java), BeanUtils.findPrimaryConstructor(OneConstructorWithoutDefaultOne::class.java))
}
class Foo(val param1: String, val param2: Int)
class Bar(val param1: String, val param2: Int = 12)

View File

@ -102,7 +102,8 @@ public class FieldError extends ObjectError {
@Override
public String toString() {
return "Field error in object '" + getObjectName() + "' on field '" + this.field +
"': rejected value [" + this.rejectedValue + "]; " + resolvableToString();
"': rejected value [" + ObjectUtils.nullSafeToString(this.rejectedValue) + "]; " +
resolvableToString();
}
@Override

View File

@ -0,0 +1,65 @@
/*
* Copyright 2002-2017 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.core;
import java.lang.annotation.Annotation;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
/**
* A common delegate for detecting Kotlin's presence and for identifying Kotlin types.
*
* @author Juergen Hoeller
* @author Sebastien Deleuze
* @since 5.0
*/
@SuppressWarnings("unchecked")
public abstract class KotlinDetector {
@Nullable
private static final Class<? extends Annotation> kotlinMetadata;
static {
Class<?> metadata;
try {
metadata = ClassUtils.forName("kotlin.Metadata", KotlinDetector.class.getClassLoader());
}
catch (ClassNotFoundException ex) {
// Kotlin API not available - no Kotlin support
metadata = null;
}
kotlinMetadata = (Class<? extends Annotation>) metadata;
}
/**
* Determine whether Kotlin is present in general.
*/
public static boolean isKotlinPresent() {
return (kotlinMetadata != null);
}
/**
* Determine whether the given {@code Class} is a Kotlin type
* (with Kotlin metadata present on it).
*/
public static boolean isKotlinType(Class<?> clazz) {
return (kotlinMetadata != null && clazz.getDeclaredAnnotation(kotlinMetadata) != null);
}
}

View File

@ -16,7 +16,6 @@
package org.springframework.core;
import java.lang.annotation.Annotation;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.util.List;
@ -27,7 +26,6 @@ import kotlin.reflect.KParameter;
import kotlin.reflect.jvm.ReflectJvmMapping;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
/**
* {@link ParameterNameDiscoverer} implementation which uses Kotlin's reflection facilities
@ -41,27 +39,13 @@ import org.springframework.util.ClassUtils;
*/
public class KotlinReflectionParameterNameDiscoverer implements ParameterNameDiscoverer {
@Nullable
private static final Class<?> kotlinMetadata;
static {
Class<?> metadata;
try {
metadata = ClassUtils.forName("kotlin.Metadata", KotlinReflectionParameterNameDiscoverer.class.getClassLoader());
}
catch (ClassNotFoundException ex) {
// Kotlin API not available - no special support for Kotlin class instantiation
metadata = null;
}
kotlinMetadata = metadata;
}
@Override
@Nullable
public String[] getParameterNames(Method method) {
if (!useKotlinSupport(method.getDeclaringClass())) {
if (!KotlinDetector.isKotlinType(method.getDeclaringClass())) {
return null;
}
try {
KFunction<?> function = ReflectJvmMapping.getKotlinFunction(method);
return (function != null ? getParameterNames(function.getParameters()) : null);
@ -74,9 +58,10 @@ public class KotlinReflectionParameterNameDiscoverer implements ParameterNameDis
@Override
@Nullable
public String[] getParameterNames(Constructor<?> ctor) {
if (!useKotlinSupport(ctor.getDeclaringClass())) {
if (!KotlinDetector.isKotlinType(ctor.getDeclaringClass())) {
return null;
}
try {
KFunction<?> function = ReflectJvmMapping.getKotlinFunction(ctor);
return (function != null ? getParameterNames(function.getParameters()) : null);
@ -103,13 +88,4 @@ public class KotlinReflectionParameterNameDiscoverer implements ParameterNameDis
return parameterNames;
}
/**
* Return true if Kotlin is present and if the specified class is a Kotlin one.
*/
@SuppressWarnings("unchecked")
private static boolean useKotlinSupport(Class<?> clazz) {
return (kotlinMetadata != null &&
clazz.getDeclaredAnnotation((Class<? extends Annotation>) kotlinMetadata) != null);
}
}

View File

@ -37,7 +37,6 @@ import kotlin.reflect.jvm.ReflectJvmMapping;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
/**
* Helper class that encapsulates the specification of a method parameter, i.e. a {@link Method}
@ -58,22 +57,6 @@ import org.springframework.util.ClassUtils;
*/
public class MethodParameter {
@Nullable
private static final Class<?> kotlinMetadata;
static {
Class<?> metadata;
try {
metadata = ClassUtils.forName("kotlin.Metadata", MethodParameter.class.getClassLoader());
}
catch (ClassNotFoundException ex) {
// Kotlin API not available - no Kotlin support
metadata = null;
}
kotlinMetadata = metadata;
}
private final Executable executable;
private final int parameterIndex;
@ -353,16 +336,7 @@ public class MethodParameter {
*/
public boolean isOptional() {
return (getParameterType() == Optional.class || hasNullableAnnotation() ||
(useKotlinSupport(this.getContainingClass()) && KotlinDelegate.isNullable(this)));
}
/**
* Return true if Kotlin is present and if the specified class is a Kotlin one.
*/
@SuppressWarnings("unchecked")
private static boolean useKotlinSupport(Class<?> clazz) {
return (kotlinMetadata != null &&
clazz.getDeclaredAnnotation((Class<? extends Annotation>) kotlinMetadata) != null);
(KotlinDetector.isKotlinType(getContainingClass()) && KotlinDelegate.isOptional(this)));
}
/**
@ -754,9 +728,10 @@ public class MethodParameter {
private static class KotlinDelegate {
/**
* Check whether the specified {@link MethodParameter} represents a nullable Kotlin type or not.
* Check whether the specified {@link MethodParameter} represents a nullable Kotlin type
* or an optional parameter (with a default value in the Kotlin declaration).
*/
public static boolean isNullable(MethodParameter param) {
public static boolean isOptional(MethodParameter param) {
Method method = param.getMethod();
Constructor<?> ctor = param.getConstructor();
int index = param.getParameterIndex();
@ -774,13 +749,12 @@ public class MethodParameter {
}
if (function != null) {
List<KParameter> parameters = function.getParameters();
return parameters
KParameter parameter = parameters
.stream()
.filter(p -> KParameter.Kind.VALUE.equals(p.getKind()))
.collect(Collectors.toList())
.get(index)
.getType()
.isMarkedNullable();
.get(index);
return (parameter.getType().isMarkedNullable() || parameter.isOptional());
}
}
return false;

View File

@ -57,6 +57,7 @@ import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.FatalBeanException;
import org.springframework.context.ApplicationContext;
import org.springframework.core.KotlinDetector;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
@ -762,7 +763,7 @@ public class Jackson2ObjectMapperBuilder {
}
// Kotlin present?
if (ClassUtils.isPresent("kotlin.Metadata", this.moduleClassLoader)) {
if (KotlinDetector.isKotlinPresent()) {
try {
Class<? extends Module> kotlinModule = (Class<? extends Module>)
ClassUtils.forName("com.fasterxml.jackson.module.kotlin.KotlinModule", this.moduleClassLoader);

View File

@ -198,11 +198,22 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
WebDataBinderFactory binderFactory, NativeWebRequest webRequest) throws Exception {
MethodParameter nestedParameter = parameter.nestedIfOptional();
Class<?> type = nestedParameter.getNestedParameterType();
Class<?> clazz = nestedParameter.getNestedParameterType();
Constructor<?> ctor = BeanUtils.findPrimaryConstructor(type);
Constructor<?> ctor = BeanUtils.findPrimaryConstructor(clazz);
if (ctor == null) {
throw new IllegalStateException("No primary constructor found for " + type.getName());
Constructor<?>[] ctors = clazz.getConstructors();
if (ctors.length == 1) {
ctor = ctors[0];
}
else {
try {
ctor = clazz.getDeclaredConstructor();
}
catch (NoSuchMethodException ex) {
throw new IllegalStateException("No primary or default constructor found for " + clazz, ex);
}
}
}
Object attribute = constructAttribute(ctor, attributeName, binderFactory, webRequest);
@ -263,8 +274,13 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
}
}
try {
args[i] = (value != null ?
binder.convertIfNecessary(value, paramType, new MethodParameter(ctor, i)) : null);
MethodParameter methodParam = new MethodParameter(ctor, i);
if (value == null && methodParam.isOptional()) {
args[i] = (methodParam.getParameterType() == Optional.class ? Optional.empty() : null);
}
else {
args[i] = binder.convertIfNecessary(value, paramType, methodParam);
}
}
catch (TypeMismatchException ex) {
bindingFailure = true;

View File

@ -21,6 +21,7 @@ import java.lang.annotation.Annotation;
import java.lang.reflect.Constructor;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import reactor.core.publisher.Mono;
import reactor.core.publisher.MonoProcessor;
@ -196,15 +197,29 @@ public class ModelAttributeMethodArgumentResolver extends HandlerMethodArgumentR
}
private Mono<?> createAttribute(
String attributeName, Class<?> attributeType, BindingContext context, ServerWebExchange exchange) {
String attributeName, Class<?> clazz, BindingContext context, ServerWebExchange exchange) {
Constructor<?>[] ctors = attributeType.getConstructors();
if (ctors.length != 1) {
// No standard data class or standard JavaBeans arrangement ->
// defensively go with default constructor, expecting regular bean property bindings.
return Mono.just(BeanUtils.instantiateClass(attributeType));
Constructor<?> ctor = BeanUtils.findPrimaryConstructor(clazz);
if (ctor == null) {
Constructor<?>[] ctors = clazz.getConstructors();
if (ctors.length == 1) {
ctor = ctors[0];
}
else {
try {
ctor = clazz.getDeclaredConstructor();
}
catch (NoSuchMethodException ex) {
throw new IllegalStateException("No primary or default constructor found for " + clazz, ex);
}
}
}
Constructor<?> ctor = ctors[0];
return constructAttribute(ctor, attributeName, context, exchange);
}
private Mono<?> constructAttribute(Constructor<?> ctor, String attributeName,
BindingContext context, ServerWebExchange exchange) {
if (ctor.getParameterCount() == 0) {
// A single default constructor -> clearly a standard JavaBeans arrangement.
return Mono.just(BeanUtils.instantiateClass(ctor));
@ -237,7 +252,13 @@ public class ModelAttributeMethodArgumentResolver extends HandlerMethodArgumentR
}
}
value = (value instanceof List ? ((List<?>) value).toArray() : value);
args[i] = binder.convertIfNecessary(value, paramTypes[i], new MethodParameter(ctor, i));
MethodParameter methodParam = new MethodParameter(ctor, i);
if (value == null && methodParam.isOptional()) {
args[i] = (methodParam.getParameterType() == Optional.class ? Optional.empty() : null);
}
else {
args[i] = binder.convertIfNecessary(value, paramTypes[i], methodParam);
}
}
return BeanUtils.instantiateClass(ctor, args);
});

View File

@ -69,6 +69,7 @@ import org.springframework.beans.propertyeditors.CustomDateEditor;
import org.springframework.context.annotation.AnnotationConfigUtils;
import org.springframework.core.MethodParameter;
import org.springframework.core.convert.converter.Converter;
import org.springframework.format.support.DefaultFormattingConversionService;
import org.springframework.format.support.FormattingConversionServiceFactoryBean;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
@ -99,6 +100,7 @@ import org.springframework.tests.sample.beans.TestBean;
import org.springframework.ui.ExtendedModelMap;
import org.springframework.ui.Model;
import org.springframework.ui.ModelMap;
import org.springframework.util.Assert;
import org.springframework.util.MultiValueMap;
import org.springframework.util.SerializationTestUtils;
import org.springframework.util.StringUtils;
@ -1761,6 +1763,30 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
assertEquals("value1-true-3", response.getContentAsString());
}
@Test
public void dataClassBindingWithOptionalParameter() throws Exception {
initServletWithControllers(ValidatedDataClassController.class);
MockHttpServletRequest request = new MockHttpServletRequest("GET", "/bind");
request.addParameter("param1", "value1");
request.addParameter("param2", "true");
request.addParameter("optionalParam", "8");
MockHttpServletResponse response = new MockHttpServletResponse();
getServlet().service(request, response);
assertEquals("value1-true-8", response.getContentAsString());
}
@Test
public void dataClassBindingWithMissingParameter() throws Exception {
initServletWithControllers(ValidatedDataClassController.class);
MockHttpServletRequest request = new MockHttpServletRequest("GET", "/bind");
request.addParameter("param1", "value1");
MockHttpServletResponse response = new MockHttpServletResponse();
getServlet().service(request, response);
assertTrue(response.getContentAsString().contains("field 'param2'"));
}
@Test
public void dataClassBindingWithConversionError() throws Exception {
initServletWithControllers(ValidatedDataClassController.class);
@ -3390,10 +3416,12 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
public int param3;
@ConstructorProperties({"param1", "param2"})
public DataClass(String param1, boolean p2) {
@ConstructorProperties({"param1", "param2", "optionalParam"})
public DataClass(String param1, boolean p2, Optional<Integer> optionalParam) {
this.param1 = param1;
this.param2 = p2;
Assert.notNull(optionalParam, "Optional must not be null");
optionalParam.ifPresent(integer -> this.param3 = integer);
}
public void setParam3(int param3) {
@ -3418,6 +3446,7 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
LocalValidatorFactoryBean vf = new LocalValidatorFactoryBean();
vf.afterPropertiesSet();
binder.setValidator(vf);
binder.setConversionService(new DefaultFormattingConversionService());
}
@RequestMapping("/bind")